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There were lots of sunspots at solar max in 2001. However, during the following "deep" solar min, sunspots were very rare for several years... as shown here in June of 2009.
Click on image for full sizeImages courtesy of SOHO/NASA/ESA.

Where have all the sunspots gone?

The Sun seems especially tidy these days - it has been virtually spotless for the last couple of years! Actually, the sunspots that periodically appear on the face of the Sun are an indicator of solar activity level, which typically waxes and wanes over the course of an 11-year cycle. This time around, however, the period when sunspots are at their minimum has lasted far longer than expected and has produced an extreme lull in the number of sunspots.

The current (as of June 2009) dearth of sunspots is very unusual. The current "solar min" is the "deepest" in nearly a century, and is the most extreme yet in the modern era since spacecraft became available to monitor the Sun in various wavelengths. No sunspots were observed on 73% of days in 2008, making it the most spot-free year since 1913. This minimum is also lasting longer than usual; the "11-year cycle" that began in 1996 is just now showing signs of ending in its 13th year.

As the current "solar min" ramps up to the next "solar max", scientists are trying to determine whether this extreme lull will presage an especially intense, an extremely weak, or a more-or-less normal uptick in solar activity. Using a technique called helioseismology to detect enormous "jet streams" of plasma flowing beneath the surface, scientists believe they have detected the stirrings of the next "solar max".

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